2018/02/21 by Marisa Giuffrida, Giuffrida, Marisa, François Holtz +5
Earth and Planetary Sciences · Environmental Science · #CO2 Sequestration and Geologic Interactions #FOS: Physical sciences #Geological and Geochemical Analysis #Geophysics (physics.geo-ph) #High-pressure geophysics and materials
paper · pdf · doi:10.48550/arxiv.1802.07656
openalex publication_date 2018/02/21 · openalex created_date 2022/09/28 · openalex updated_date 2026/07/28
Changes in magmatic assemblages and crystal stability as a response of CO2\nflushing in basaltic systems have been never directly addressed experimentally,\nmaking the role of CO2 in magma dynamics still controversial and object of\nscientific debate. We conducted a series of experiments to understand the\nresponse of magmas from Etna volcano to CO2 flushing. We performed a first\nexperiment at 300 MPa to synthesize a starting material composed of crystals of\nsome hundreds of m and melt pools. This material is representative of an\ninitial magmatic assemblage composed of plagioclase, clinopyroxene and a water\nundersaturated melt. In a second step, the initial assemblage was equilibrated\nat 300 and 100 MPa with fluids having different XCO2fl . Our experiments\ndemonstrate that flushing basaltic systems with fluids may drastically affect\ncrystal textures and phase equilibria depending on the amount of H2O and CO2 in\nthe fluid phase. Since texture and crystal proportions are among the most\nimportant parameters governing the rheology of magmas, fluid flushing will also\ninfluence magma ascent to the Earths surface. The experimental results open new\nperspectives to decipher the textural and compositional record of minerals\nobserved in volcanic rocks from Mt. Etna, and at the same time offer the basis\nfor interpreting the information preserved in minerals from other basaltic\nvolcanoes erupting magmas enriched in CO2.\n